Interface accessory for use with an aerosol inhalation system

ABSTRACT

According to one aspect of the present invention, an accessory for an aerosol inhalation system includes a main conduit body having an outlet end for placement close to a mouth of a patient, and first and second leg conduits that are in fluid communication with the main conduit body. The accessory further includes a holding chamber having a first compartment and a second compartment separated from the first compartment, with the first compartment being sealingly and fluidly coupled to the one port associated with the first leg conduit and the second compartment is sealingly and fluidly coupled to a port associated with the second leg conduit. An arrangement of valves is provided for directing fluid along prescribed flow paths depending on whether the patient inhales or exhales.

CROSS-REFERENCE TO RELATED APPLICATION

The present application is a continuation-in-part of U.S. patentapplication Ser. No. 11/121,688, filed May 3, 2005, which is herebyincorporated by reference in its entirety.

TECHNICAL FIELD

The present invention relates to inhalation equipment and moreparticularly, relates to aerosol inhalation systems including aninterface (accessory) for use in the system between a conventional partof the inhalation equipment, such as a generator, and the patient toprovide in a number of applications a completely closed system thatensures that the medication delivered to the patient has a fixedconcentration over time.

BACKGROUND

Aerosol inhalation equipment is commonly used as a means to delivermedication in an aerosolized form to a patient. Aerosolized medicationis typically used to treat patients with respiratory conditions, such asasthma or chronic obstructive pulmonary disease (COPD). For example,inhalation equipment is a common means for delivering medication tocounter certain aliments of a patient population, including reactiveairway disease, asthma, cystic fibrosis, etc.

It is generally accepted that effective administration of medication asaerosol depends on the delivery system and its position in relation tothe patient. Aerosol particle deposition is influenced by particle size,ventilatory pattern, and airway architecture and effective medicationresponse is also influenced by the dose of the medication used.

An aerosol delivery system includes three principal elements, namely agenerator, a power source, and an interface. Generators include smallvolume nebulizers (SVN), large volume nebulizers (LVN), metered doseinhalers (MDI), and dry powder inhalers (DPI). The power source is themechanism by which the generator operates or is actuated and includescompressed gas for SVN and LVN and self-contained propellants for MDI.The interface is the conduit between the generator and the patient andincludes spacer devices/accessory devices with mouthpieces or facemasks. Depending on the patient's age (ability) and coordination,various interfaces are used in conjunction with SVN and MDI in order tooptimize drug delivery.

A SVN is a jet nebulizer that is powered by a compressed gas source. Themedication is displaced up a capillary tube from the nebulizer'sreservoir and is dispersed continuously as aerosolized particles. Theaerosolized particles are spontaneously inhaled by the patient ordelivered in conjunction with positive-pressure breaths. Typically, forpatients greater than 3 years who are spontaneously breathing without anartificial airway and are able to cooperate, a mouthpiece with anextension reservoir should be used. For patients unable to negotiate amouthpiece, typically children under 3 years, a face mask should beused.

An MDI is essentially a pressurized canister that contains a medicationand propellant. Actuation of the MDI results in the ejection of one doseof medication as aerosolized particles, which can be spontaneouslyinhaled by the patient or delivered in conjunction withpositive-pressure breaths. A spacer device/accessory device should beused with an MDI. A spacer device enhances delivery by decreasing thevelocity of the particles and reducing the number of large particles. Aspacer device with a one-way valve, i.e., holding chamber, eliminatesthe need for the patient to coordinate actuation and inhalation andoptimizes drug delivery. A spacer device without valves requirescoordination between inhalation and actuation. The MDI with spacerdevice and face mask is appropriate for patients, typically less than 3years, unable to use a mouthpiece.

A DPI is a breath-actuated device that uses a gelatin capsule containinga single dose of medication and a carrier substance to aid in thedispersion of the drug. The capsule is inserted into the device andpunctured. The patient's inspiratory flow disperses the dry particlesand draws them into the lower airways. In spontaneously breathingpatients, this device is appropriate in patients who are able to achievea certain inspiratory flow, such as equal to or greater than 50 L/min.This will typically correspond to children about 6 years or greater.

A LVN can be used to deliver a dose of medication continuously over aperiod of time. A LVN is powered by a compressed gas source, and a facemask is typically used as the interface.

The two primary means for delivering aerosolized medication to treat amedical condition is an MDI or a nebulizer. MDI medication (drug)canisters are typically sold by manufacturers with a boot that includesa nozzle, an actuator, and a mouthpiece. Patients can self-administerthe MDI medication using the boot alone but the majority of patientshave difficulty in synchronizing the actuation of the MDI canister andpatient inhalation and improve the delivery and improve the delivery ofmedication by decreasing oropharyngeal deposition of the aerosol drug.

Many valved chambers of this type are commercially available. Examplesof such spacers include but are not limited to those structuresdisclosed in U.S. Pat. Nos. 4,470,412; 5,012,803; 5,385,140; 4,637,528;4,641,644; 4,953,545; and U.S. patent application publication No.2002/0129814. These devices are expensive and may be suitable forchronic conditions that require frequent use of MDI inhalers providedthe cost and labor involved in frequent delivery of medication isacceptable to the patient. However, under acute symptoms, such devicesmay fail to serve the purpose and lead to an inadequate delivery ofmedication.

Aerosol delivery systems that use standard small volume nebulizers arecommonly used in acute conditions as they are cheap and overcome theinhalation difficulties associated with actuation of MDI andsynchronization of inhalation by the patient. Nebulizers are fraughtwith numerous problems as well. The medication dose used is about 10times of that used with an MDI and hence the increased cost without anyadded proven clinical benefit. Secondly, the majority of the nebulizedmedication is wasted during exhalation. Thirdly, the time taken todeliver the medication is several times that of an MDI and the laborcost of respiratory therapist may outweigh the benefits of nebulizerscompared with MDIs. Breath actuated nebulizers(s) with reservoir havebeen designed to overcome the medication waste. An example of this typeof device is found in U.S. Pat. No. 5,752,502. However, these devicesare expensive and still have all the other problems associated withnebulizer use alone. Other examples of aerosol inhalation devices can befound in U.S. Pat. No. 4,210,155, in which there is a fixed volume mistaccumulation chamber for use in combination with a nebulizer and a TEEconnection.

Problems with prior art devices include that the devices significantlywaste medication, they provide a non-uniform concentration of deliveredmedication, they are expensive, and they are difficult to use. Many ofthese devices are commercially available in which the nebulizer isdirectly attached to the TEE connector without any mixing chamber. Allof the aforementioned devices can be used with either an MDI or anebulizer but not both, and hence, face the difficulty associated witheither system alone. Other devices have tried to overcome the aboveproblems by incorporating a mixing chamber in the device withadaptability to be used with an MDI or standard nebulizer. U.S. patentapplication publication No. 2002/0121275 disclosed a device having theabove characteristics. However, this device is plagued with problemsthat are typical to those type of devices. As with other conventionaldevices, the disclosed device, like the other ones, fails to incorporatesome of the key features necessary for enhanced aerosol delivery.

In general, each of the prior art devices suffers from the followingdeficiencies: (1) the entrained airflow in the device interferes withthe MDI plume as well as the plume generated by a nebulizer resulting inincreased impaction losses of aerosol generated by either an MDI ornebulizer; (2) the device does not have the ability to deliver a desiredprecise fraction of inspired oxygen to a hypoxic patient andsimultaneously deliver aerosol medication with either a metered doseinhaler (MDI) or a nebulizer; (3) the device can not deliver a gas witha desired density to improve aerosol delivery and a desired fraction ofinspired oxygen to a hypoxemic patient; (4) the device does not have theability to deliver different density gases with a desired fraction ofinspired oxygen simultaneously while retaining the ability to deliveraerosol medication at the same time with either an MDI or a nebulizer;(5) the device does not have the ability to deliver a mixture ofmultiple gases to a patient and simultaneously maintain a desiredfraction of inspired oxygen; (6) the device does not serve as a facemaskfor delivering varying concentrations of inspired oxygen from room airto 100% but serves solely as an aerosol delivery device; (7) the devicedoes not have a reservoir chamber—either as a bag or as a large volumetubing to store nebulized medication that is otherwise wasted duringexhalation (The holding chamber of this type of device varies from 90 ccto 140 cc and is not enough to serve as a reservoir for the volume ofnebulized medication generated during exhalation is wasted); (8) thereis no mechanism in the device to prevent entrainment of room air whichforms the bulk of volume during inhalation (the fraction of inspiredoxygen and the density of the gas mixture inhaled by the patient mayvary with every breath with the device depending on the volume ofentrained room air which may vary with each breath); (9) the device doesnot have any valve system to prevent exhaled carbon dioxide fromentering the holding chamber—rebreathing of carbon dioxide from theholding chamber on subsequent inhalation can be extremely detrimental toa patient and extremely dangerous under certain clinical conditions;(10) the device does not have the capability of delivering medicationwith an MDI and a nebulizer simultaneously; and (11) the device has afixed volume-holding chamber, which makes the device extremely large andcumbersome to deliver medication.

What is needed in the art and has heretofore not been available is asystem that overcomes the above deficiencies and incorporatesfunctionality to make the device a compact, user friendly, economical,and multipurpose aerosol device for both acute and chronic use witheither an MDI or a nebulizer or with both devices simultaneously aswarranted by the patient's clinical circumstances.

SUMMARY

According to one aspect of the present invention, an accessory for anaerosol inhalation system includes a main conduit body having an outletend for placement close to a mouth of a patient, and first and secondleg conduits in fluid communication with the main conduit body. Each ofthe first and second leg conduits includes a distal end and the secondleg conduit is spaced apart from the first leg conduit.

The accessory includes a first port formed as part of the first legconduit for attachment to a device that generates aerosol particles as ameans for delivering medication to the patient. A second port formed aspart of the first leg conduit, while a third port is formed as part ofthe second leg conduit. The accessory further includes a holding chamberhaving a first compartment and a second compartment separated from thefirst compartment, with the first compartment being sealingly andfluidly coupled to the second port and the second compartment beingsealingly and fluidly coupled to the third port.

An arrangement of valves is provided such that when the patient exhales,the first leg conduit is sealingly closed off from both the main conduitbody and the second leg conduit resulting in the aerosol particlesflowing into and being held in the first compartment of the holdingchamber. Conversely, when the patient inhales, the first leg conduit isopened to the main conduit body and in fluid communication with thesecond leg conduit resulting in the aerosol particles delivered throughthe first port being delivered to the patient.

According to another aspect of the present invention, an aerosolinhalation system includes the above described accessory and furtherincludes at least one device for producing aerosol particles to delivermedication to a patient through a piece of equipment in communicationwith a respiratory system of the patient. The accessory is in the formof an interface between the at least one device and the piece ofequipment and includes (1) a main conduit body having an outlet endconnected to the piece of equipment; (2) a first leg conduit in fluidcommunication with the main conduit body; and (3) a second leg conduitin fluid communication with the main conduit body, with the second legconduit being spaced apart from the first leg conduit. The accessoryalso includes a first port formed as part of the first leg conduit forattachment to the at least one device, a second port formed as part ofthe first leg conduit; and a third port formed as part of the second legconduit.

The accessory also has a holding chamber defined by a first compartmentand a second compartment separated from the first compartment. The firstcompartment is sealingly and fluidly coupled to the second port and thesecond compartment is sealingly and fluidly coupled to the third port.Associated with the accessory is an arrangement of valves including afirst valve and a second valve. The first valve opens up the first legconduit to the main conduit body under a first prescribed event andcloses the second leg conduit to the main conduit body under a secondprescribed event. The second valve is provided for venting the secondleg conduit under the second prescribed event.

A supplemental gas source is provided in selective communication withthe second compartment for delivering supplemental gas under prescribedconditions. The supplemental gas source includes a third valve forcontrolling a flow rate of the supplemental gas into the secondcompartment.

Further aspects and features of the exemplary aerosol inhalation systemdisclosed herein can be appreciated from the appended Figures andaccompanying written description.

BRIEF DESCRIPTION OF THE DRAWING FIGURES

The foregoing and other features of the present invention will be morereadily apparent from the following detailed description and drawings ofthe illustrative embodiments of the invention wherein like referencenumbers refer to similar elements and in which:

FIG. 1 is a side perspective view of an accessory for use in an aerosolinhalation system according to a first embodiment;

FIG. 2 is a cross-sectional view taken along the line 2-2 of FIG. 1;

FIG. 3 is a cross-sectional view taken along the line 3-3 of FIG. 2;

FIG. 4 is a cross-sectional view taken along the line 4-4 of FIG. 2;

FIG. 5 is a cross-sectional view taken along the line 5-5 of FIG. 4.

FIG. 6 is a perspective view of an accessory for use in an aerosolinhalation system according to a second embodiment;

FIG. 7 is a perspective view of an accessory for use in an aerosolinhalation system according to a third embodiment;

FIG. 8 is a partial cross-sectional view taken along the line 8-8 ofFIG. 6;

FIG. 9 is a partial cross-sectional view taken along the line 9-9 ofFIG. 6; and

FIG. 10 is a partial cross-sectional view taken along the line 10-10 ofFIG. 6.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Now turning to FIGS. 1-5 in which an accessory or interface element 100according to one exemplary embodiment and for use in an aerosol deliverysystem is illustrated. As described below, the accessory 100 is intendedfor use with a nebulizer or an MDI or another piece of aerosolinhalation equipment. The accessory 100 is defined by a body 110 thatcan be formed of any number of different materials, including a plasticmaterial or a metal. The accessory 100 is essentially a hollow body 110that has a first end (inlet end) 112 and an opposing second end (outletend) 114. The accessory 100 is intended to act as a fluid connector inthat it is fluidly attached to another piece of equipment, such as afacemask, that is directly coupled to the patient's mouth, as well asbeing fluidly attached to an actuatable device that generates theaerosol particles (aerosolized medication) that are delivered to thepatient.

In the illustrated embodiment, the accessory 100 is in the form of atubular Y-shaped connector and therefore the body 110 is defined by amain conduit portion 120 and a first leg conduit 130 and a second legconduit 140, with the first and second leg conduits 130, 140 beingfluidly connected to the main conduit portion 120. FIG. 2 is across-sectional view which illustrates the Y-shaped nature of theconduits with the first and second leg conduits 130, 140 being spacedthereapart. The first and second leg conduits 130, 140 are substantiallyparallel to one another. The body 110 can also be thought of as havingan upper or top surface or face 116 and an opposing lower or bottomsurface or face 118. In the illustrated embodiment, the accessory body110 is shown as having a circular cross-section; however, it will beappreciated that the body 110 can have any number of othercross-sectional shapes.

The main conduit portion 120 therefore has an open first end 122 and asecond end 124 which interfaces and is fluidly connected to the firstand second leg conduits 130, 140. The first leg conduit 130 has a firstend 132 that interfaces with the second end 124 and an opposing opensecond-end 134. The second-leg conduit 140 has a first end 142 thatinterfaces with the second end 124 and an opposing open second end 144which is adjacent the open second end 134 of the first leg conduit 130.The main conduit portion 120 is the part of the accessory that isintended to be connected to equipment that is placed over the patient'smouth and in one preferred embodiment, the main conduit portion 120engages and sealingly couples with a facemask that is intended forplacement over the patient's nose and mouth. Thus, the main conduitportion 120 is the principal pathway for fluid, such as air and theaerosol particles, to either enter the patient in the case of theaerosol particles and air or be discharged from the patient as in thecase of exhaled gases, such as carbon dioxide.

The body 110 includes a plurality of ports or interface members orregions that permit a part to be fluidly connected to the body 110. Inthe illustrated embodiment, the body 110 includes three ports formed asa part of the body 110. More specifically, a first port 150 is formed asa part of the first leg conduit 130 and therefore is in fluidcommunication with an interior of the first leg conduit 130. The firstport 150 thus has an opening 152 that defines an entrance into the firstleg conduit 130 and typically, includes a stem, boss or the like 154that defines the opening 152 and permits a member to be sealinglyattached to the first leg conduit 130 and in fluid communication withthe interior of the first leg conduit 130. Preferably, the first port150 is formed on the bottom surface or face 118. The first port 150 islocated closer to and preferably is proximate to or adjacent the opensecond end 134 of the first leg conduit 130.

Similarly, the second port 160 is formed as a part of the first legconduit 130 and therefore is in fluid communication with an interior ofthe first leg conduit 130. The second port 160 thus has an opening 162that defines an entrance into the first leg conduit 130 and typically,includes a stem, boss or the like 164 that defines the opening 162 andpermits a member to be sealingly attached to the second leg conduit 140and in fluid communication with the interior of the first leg conduit130. Preferably, the second port 160 is formed on the bottom surface orface 118. The second port 160 is located closer to and preferably isproximate or adjacent the first end 132 of the first leg conduit 130,with the first port 150 being formed between the second port 160 and theopen second end 134.

Unlike the first and second ports 150, 160, a third port 170 is formedas a part of the second leg conduit 140 and therefore is in fluidcommunication with an interior of the second leg conduit 140. The thirdport 170 thus has an opening 172 that defines an entrance into thesecond leg conduit 140 and typically, includes a stem, boss or the like174 that defines the opening 172 and permits a member to be sealinglyattached to the second leg conduit 140 and in fluid communication withthe interior of the second leg conduit 140. Preferably, the third port170 is formed on the bottom surface or face 118. While the location ofthe third port 170 is not critical, the illustrated third port 170,which is exemplary in nature, is located closer to and preferably isproximate to or adjacent the first end 142 of the second leg conduit140. In the illustrated embodiment, the second port 160 and the thirdport 170 are generally aligned with one another and are essentiallyspaced apart from one another.

In one particularly preferred embodiment, the accessory 100 is intendedfor use with a nebulizer, generally indicated at 200, and thereforeincludes a holding chamber 300 into which the aerosol particles can bestored prior to the patient inhaling. The holding chamber 300 ispreferably formed as a member that is collapsible and expandabledepending upon whether gas is being delivered thereto or being evacuatedtherefrom. The holding chamber 300 thus can have a number of differentstructures that have a variable dimension, such as a variable length ora variable width. In one embodiment, the holding chamber 300 is definedby a bellows-type structure that can either expand or collapse/constrictdepending upon the force applied. As with other accessories of thistype, the holding chamber 300 is intended to receive and store theaerosol particles prior to the patient inhaling them by means of theaccessory 100 and the facemask.

In the illustrated embodiment, the holding chamber 300 is in the form ofan expandable/collapsible bag (reservoir bag). According to one aspectof the present invention, the holding chamber 300 is in the form of abi-furcated bag or the like 310 as shown in FIG. 1. More specifically,the bag 310 is bi-furcated and has two independent distinctcompartments, namely a first compartment 320 and a second compartment330. Since the two compartments 320, 330 are distinct from one another(no fluid communication therebetween), the bag 310 has a first port 340that forms an entrance and is in fluid communication with the firstcompartment 320, as well as a second port 350 that forms an entrance andis in fluid communication the second compartment 330. A separating wallor membrane 360 is formed as part of the bag 310 and serves to dividethe bag 310 into the first and second compartments 320, 330. The body ofthe bag 310, as well as the separating wall 360, is preferable formed ofa flexible material, such as a fabric that permits the bag 310 to eitherexpand as when fluid enters the bag 310 or contract (collapse) as whenthe fluid is evacuated from the bag 310. The first port 340 is formed onone side of the separating wall 360, while the second port 350 is formedon the other side of the separating wall 360. Similar to the third port170 and complementary thereof, the second port 350 is typically definedby a hollow stem or boss 352.

The first port 340 includes a complementary fastening feature 341 thatpermits it to be sealingly attached to the second port 150 of the firstleg conduit 130, and similarly, the second port 350 includes acomplementary fastening feature 351 that permits it to be sealinglyattached to the third port 170 of the second leg conduit 140. Forexample, the first and second fastening features 341, 351 can be in theform of threads that mate with complementary threads that are part ofthe second and third ports 150, 170, respectively. Other fasteningmeans, such as locking means, can likewise be used so long as theaccessory 100, and in particular, the first and second leg conduits 130,140, is sealingly attached to the bag 310. While, the fastening features341, 351 have been shown as being threads, it will be appreciated thatin many applications and embodiments, the third port 170 and second port350 simply mate with one another via a frictional interface fit wherethe stem 352 is simply inserted into the stem 174 or vice versa.

In one embodiment, one of the first and second compartments 320, 330 isassociated with the nebulizer 200 and more particularly, serves as aholding chamber for the nebulized medication that is generated by thenebulizer 200. The other of the compartments 320, 330 is associated witha supplemental gas source and serves as a supplemental gas holdingchamber that supplements the nebulized medication when needed asexplained in detail below.

While the two compartments 320, 330 of the bag 310 are illustrated ashaving equal or about equal volumes, it will be appreciated that the bag310 can be constructed so that one of the compartments 320, 330 has agreater volume. For example, the first compartment 320 that serves asthe nebulizer holding compartment can have a greater volume than thesecond compartment 330 which receives the supplemental gas to backup thenebulized medication holding chamber.

When the accessory 100 is used with nebulizer 200, the open second end134 of the first leg conduit 130 is typically closed off or capped by acap member 180 or the like. The cap 180 is sealingly received in theopen second end 134 and serves to seal the first leg conduit 130;however, the cap 180 is preferably a removeable member.

The accessory 100 includes a number of different valve assemblies thatare positioned within the body 110. More specifically, a first valveassembly 400 is disposed within the open second end 144 of the secondleg conduit 140 and in the illustrated embodiment, the first valveassembly 400 functions as an exhalation valve. The first valve assembly400 includes a valve element 402 which is positionable between an openposition and a closed position and which can be any number of differenttype of valve structures so longer as they function in the intendedmanner and provide the desired results. The valve 402 typically seatsagainst a valve seat 404 that is formed at the second end 144 when thevalve 402 is closed. The illustrated valve 402 is a one-way flap valvethat presses against the valve seat 404 on inhalation and completelyoccludes the open second end 144 to prevent any room air entrainment(i.e., not allowing the air from the atmosphere to enter into the secondleg conduit 140 on inhalation). On exhalation, the flap valve 402 movesaway from the flap valve seat 404 for the air exhaled by the patient toescape into the atmosphere from the main conduit portion 120 by flowingthrough the second leg conduit 140 and then through the opening formedat the second end 144. The open second end 144 is the only means for theexhaled air to escape as will be appreciated below since the three ports150, 160, 170 are capped or otherwise not open and the second end 144 ofthe first leg conduit 130 is also capped or otherwise closed.

A second valve assembly 410 is provided and functions as an inhalationvalve in that the valve moves between an open position and a closedposition depending upon whether the patient is inhaling or exhaling. Thesecond valve assembly 410 is disposed within the body 110 and inparticular, the second valve assembly 410 is disposed at an interfacebetween the first leg conduit 130 and the main conduit portion 120 suchthat when the second valve assembly 410 is in an open position, fluidcan flow between the main conduit portion 120 and the first leg conduit130, while in a closed position, fluid is prevented from flowingtherebetween. In other words, the second valve assembly 410 is disposedat the first end 132 of the first leg conduit 130. The second valveassembly 410 includes a valve element 412 and typically and as with thefirst valve assembly 400, the second valve assembly 410 includes a valveseat 414 against which the valve 412 seals in the closed position.

The second valve element 412 can be any number of different one-wayvalves and in one embodiment, the second valve element 412 is a flapvalve that opens upon inhalation and conversely, closes upon exhalation.The second valve element 412 extends completely across theconduit/passageway of the first leg conduit 130 and therefore, thisvalve 412 serves to completely close off the first leg conduit 130 fromthe main conduit portion 120.

The second valve element 412 is located such that both the first andsecond ports 150, 160 are located between the second valve 412 and thesecond end 134 and therefore, these ports 150, 160 are completely closedoff from the main conduit portion 120 when the second valve element 412is in the closed position.

In the illustrated embodiment, all three of the ports 150, 160, 170 arelocated on the bottom face 118 of the body 110. The first port 150 isintended to be fluidly attached to the device that generates the aerosolparticles (medication) that is delivered to the patient and preferably,as illustrated, the first port 150 is fluidly connected to the nebulizer200. More specifically, a connector 212 of a conduit (tube) 210 of thenebulizer 200 is sealingly attached to the first port 150 so that thenebulized medication is delivered through the conduit 210 and into theinterior of the first leg conduit 130 and when the second valve element412 is open, the nebulized medication (aerosol particles) travel thelength of the first leg conduit 130 through the opening defined by thevalve seat 414 and into the main conduit portion 120 and then into theequipment (facemask) that delivers the medication to the patient. Thisis the sequence of events when the patient inhales. Conversely, when thepatient exhales, the second valve element 412 closes; however, thenebulizer 200 continues to deliver the nebulized medication through thefirst port 150 into the interior of the first leg conduit 130. Since thesecond valve element 412 is closed when the patient exhales prior to thenext inhalation, the nebulized medication can not flow into the mainconduit portion 120 but instead flows through the second port 160through the first port 340 and into the first compartment 320 of the bag310.

The interface between the nebulizer 200 and the first port 150 does nothave to be a threaded one as illustrated; but instead, can be any numberof types of interfaces. One preferred interface between the nebulizer200 and the first port 150 is merely a frictional fit interface whereone of the nebulizer stem and the body (stem) of the first port 152 isinserted into the other one.

The first compartment 320 of the bag 310 is therefore intended to act asa main reservoir bag in that the first compartment 320 receives andholds the nebulized medication until the patient inhales. The firstcompartment 320 of the bag 310 thus expands until the patient inhales atwhich time the second valve element 412 opens and the inhalation of thepatient draws the nebulized medication out of the first compartment 320into the first conduit leg 130 then into the main conduit body 120 whereit is delivered to the patient. In FIGS. 4 and 5, the solid lines showthe first and second compartments 320, 330 in a condition where only thefirst compartment 320 is significantly expanded.

There are some circumstances where an insufficient amount of nebulizedmedication is present in the first compartment 320 of the bag 310. Thismay result because the flow rate of the nebulizer 200 is insufficientfor the patient as when the patient has a greater body weight than theflow rate setting of the nebulizer 200. When this does occur, thepatient experiences a very uncomfortable feeling in that the patientwill experience an insufficient air flow to the lungs and therefore willbegin to breathe more deeply and rapidly. In other words, the patientmay begin feeling as though they need to gasp for air to breathe.

The present invention overcomes such potential deficiency in air flow tothe patient by providing the second compartment 330 in the bag 310 whichacts as a supplemental air source for the patient due to the secondcompartment 330 being attached to a supplemental gas source, generallyindicated at 301. Preferably, the gas source 301 connects to the stem352 of the second port 350 as shown in the figures; however, it ispossible for the gas source 301 to be directly connected to the secondcompartment 330 of the bag 310. In any event, the gas source 301 isdirectly and fluidly connected to the second compartment 330 andtherefore, the gas is delivered into the second compartment 330. As withthe flow of nebulized medication into the first compartment 320, theflow of the gas source 301 into the second compartment 330 causes thesecond compartment 330 to expand as the bag 310 is filled with gas. Thisshown in FIGS. 4 and 5 by the phantom lines which show both the firstand second compartments 320, 330 significantly expanded.

It will be appreciated that the gas source 301 serves as a supplementalgas since gas stored in the second compartment 330 is in selective fluidcommunication with the main conduit member 120 and therefore, can flowto the patient under certain circumstances as discussed-below. In otherwords, if there is insufficient gas in the form of nebulized gas in thefirst compartment, when the patient inhales, then the patient will notexperience the above described breathing problems since the secondcompartment 330 is open to the patient through the main conduit portion120 and therefore, the patient can inhale the supplemental gas that ispresent in the second compartment 330 to make up for any shortfall ingas in the first compartment 320.

The gas source 301 typically has an associated valve assembly (notshown) that is external to the system 100 and is typically at the gassource 301 for controlling the flow rate of the gas source 301 into thesecond compartment 330. The valve assembly is preferably an adjustablevalve that controls the flow rate of the supplemental gas into thesecond compartment 330. Any number of different valve mechanisms aresuitable for this type of application and typically include anadjustable part, such as a dial, that permits the physician to easilyalter and change the flow characteristics. For example, the valvemechanism can include an adjustable member that when manipulated eithersequentially closes or opens the opening formed in the conduit thatdelivers the supplemental gas to the second compartment 330.

Thus, the physician can initially set the valve at one setting which thephysician believes will provide a sufficient supplemental gas flow intothe second compartment 330 based on the physician's past experiences andbased on certain characteristics of the patient, such as the size andweight of the patient. For example, when the patient is a large adult oreven a large child, the flow rate of the nebulized medication into thefirst compartment 320, even when it is set at a maximum flow rate, maynot be sufficient and therefore, this could result in the patientreceiving a low level of air and feeling the above noted discomfort. Thegas source 301 thus supplements the gas flow of the nebulizer 200 andmakes up for any deficiency so that the patient breaths smoothlythoughout the procedure.

When setting the valve, the physician will keep in mind that it may notbe desirable to set the flow rate of the supplemental gas at too high avalue since this will result in the second bag compartment 320 expandingand also, results in the supplemental gas source 301 mixing with thenebulized medication as the patient inhales, thereby causing a decreasein the inhaled concentration of the medication. As mentioned before, itis desirable to try to keep as fixed as possible the concentration ofthe inhaled medication. Since the second compartment 330 is fluidlyconnected to the second leg conduit 140 and the first valve assembly400, any excess build up of supplemental gas in the second compartment330 can be vented through the first valve 402 each time the patientexhales.

In the event that the initial setting of the valve is not optimal inthat the too much supplemental gas is being delivered to the second bagcompartment 330 or too little supplemental gas is being delivered to thesecond bag compartment 330, the physician simply needs to make thenecessary adjustment to the valve to either immediately reduce orincrease, respectively, the supplemental gas flow into the secondcompartment 330. This can be done by simply turning or otherwisemanipulating the valve. It is also very easy for the physician todetermine whether the flow rate of the supplemental gas source 301 isoptimal since the physician can observe the bag 310 and moreparticularly, can observe whether either the first compartment 320, thesecond compartment 330 or both compartments 320, 330 appear to beexcessively collapsed (thus indicating an increase in flow rate isneeded) or excessively expanded or extended (thus indicating a decreasein flow rate is needed). The physician can simply and immediately alterthe flow rate and thus, the accessory 100 is tailored to be used with awhole range of different types of patients, from small infants up tolarge adults.

A supplemental gas valve assembly 360 is provided for controlling theflow of the supplemental gas out of the second compartment 330 and intothe second leg conduit 140 and more particularly, to permit flow of thesupplemental gas from the second compartment 330 into the second legconduit 140, through the main conduit member 120 and ultimately to thepatient when the patient inhales and conversely, preventing the flow ofsupplemental gas from the second compartment 330 into the second legconduit when the patient exhales. It will also be appreciated that whenvalve assembly 360 closes during exhalation, the exhaled air thatincludes waste gases is not permitted to flow into the secondarycompartment 330 where it could then be drawn into the patient at thenext inhalation movement of the patient.

In order to accomplish this, the valve assembly 360 must be locatedabove (upstream) of the incoming supplemental gas source 301. Thus andaccording to one exemplary embodiment, the valve assembly 360 ispositioned within the stem 352 above the location where the second gassource 301 is connected to the stem 352. It will also be appreciatedthat another location for the valve assembly 360 is in the stem 174 ofthe third port 170. In either embodiment, the location of the valveassembly 360 can not interfere with the fastening or securing of thestem 352 to the stem 174. Thus, when a frictional fit is the interfacemeans for connecting the stems 352, 174, the valve assembly 360 must bedisposed in the stem that has the smaller outer diameter and which isdisposed within the larger diameter stem.

The valve assembly 360 moves between an open position and a closedposition depending upon whether the patient is inhaling or exhaling.When the valve assembly 360 is in an open position, fluid can flowbetween the second compartment 330 and the second leg conduit 140, whilein a closed position, fluid is prevented from flowing therebetween. Thevalve assembly 360 includes a valve element 362 and typically and aswith the valve assemblies 400, 410, the valve assembly 360 includes avalve seat against which the valve 362 seals in the closed position.

The valve element 362 can be any number of different one-way valves andin one embodiment, the valve element 362 is a flap valve that opens uponinhalation and conversely, closes upon exhalation. The illustrated valveelement 362 extends completely across the conduit/passageway of the stem352 above the entrance location of the gas source 301 and therefore,this valve element 362 serves to completely close off the secondcompartment 330 from the second leg conduit 140 and the main conduitportion 120 under select conditions, such as exhalation of the patient.

The above described accessory and variations thereof can be used inconventional inhalation equipment settings and thus can be used withconventional nebulizers to overcome the deficiencies that are associatedwith the prior art aerosol inhalation systems. In addition, the use of asupplemental gas source ensures that the accessory and the disclosedaerosol inhalation system is suitable for use with all types of patientsfrom small infants to large adults irregardless of whether the flow rateof the nebulizer by itself is sufficient to support a normal breathingpattern of the patient.

Now turning to FIGS. 6 and 8-10 in which an accessory or interfaceelement 500 according to one exemplary embodiment and for use in anaerosol delivery system is illustrated. As described below, theaccessory 500 is intended for use with a nebulizer or an MDI or anotherpiece of aerosol inhalation equipment. The accessory 500 is defined by abody 510 that can be formed of any number of different materials,including a plastic material or a metal. The accessory 500 isessentially a hollow body 510 that has a first end (inlet end) 512 andan opposing second end (outlet end) 514. The accessory 500 is intendedto act as a fluid connector in that it is fluidly attached to anotherpiece of equipment, such as a facemask, that is directly coupled to thepatient's mouth, as well as being fluidly attached to an actuatabledevice that generates the aerosol particles (aerosolized medication)that are delivered to the patient.

In the illustrated embodiment, the body 510 has a main section 516 thatincludes a number of arms or feet that extend outwardly therefrom, withthe inlet end 512 being formed at the end of a first leg 520 that isformed at a right angle to the main section 516. The main section 516includes a second leg 530 that extends outwardly therefrom between thefirst leg 520 and the outlet end 514 and a third leg 540 that is locatedbetween the outlet end 514 and the second leg 530. The third leg 540 islocated proximate the outlet end 514, while the second leg 530 is closerto the first leg 520. The first, second and third legs 520, 530, 540 arethus tubular structures that are in fluid communication with theinterior of the tubular main section 516 and are open at their oppositedistal ends to receive an object (such as a conduit or connector) or afluid, etc.

The main section 516 includes a fourth leg 550 that extends outwardlyfrom the main section 516 and is in fluid communication with theinterior of the main section 516. Like the other legs, the fourth leg550 is a tubular structure that is open at its distal end for anattachment to an object (conduit). In the illustrated embodiment, thefirst, second and third legs 520, 530, 540 extend outwardly from anunderside of the tubular main section 516, while the fourth leg 550extends outwardly from the opposite top side of the tubular main section516. The fourth leg 550 is located between the second and third legs530, 540.

The main section 516 is the part of the accessory 500 that is intendedto be connected to equipment that is placed over the patient's nose andmouth. Thus, the main section 516 (main conduit) is the principalpathway for fluid, such as air and the aerosol particles, to eitherenter the patient in the case of aerosol particles and air or to bedischarged from the patient as in the case of exhaled gases, such ascarbon dioxide.

The first leg 520 serves as a port or connector for mating with a device200 that generates a gas flow that is intended to be breathed in by thepatient. For example, the device 200 can be in the form of a nebulizeror even an MDI or the like. In the illustrated embodiment, the device isin the form of a nebulizer 200 that is fluidly connected to a gas sourcevia a nebulizer conduit 215. The nebulizer 200 is fluidly and sealinglyconnected to the first leg 520 so that the gas and aerosolized particlesgenerated by the nebulizer 200 are delivered into the interior of themain section 516 of the accessory 500. Any number of techniques can beused to couple the nebulizer 200 to the first leg 520, such asthreadingly, snap-fittingly, frictionally, etc., the two together.

In one embodiment, the accessory 500 is intended for use with anebulizer, generally indicated at 200, and therefore includes a holdingchamber 700 into which the aerosol particles can be stored prior to thepatient inhaling. The holding chamber 700 is preferably formed as amember that is collapsible and expandable depending upon whether gas isbeing delivered thereto or being evacuated therefrom. The holdingchamber 700 thus can have a number of different structures that have avariable dimension, such as a variable length or a variable width. Inone embodiment, the holding chamber 700 is defined by a bellows-typestructure that can either expand or collapse/constrict depending uponthe force applied. As with other accessories of this type, the holdingchamber 700 is intended to receive and store the aerosol particles priorto the patient inhaling them by means of the accessory 500 and thefacemask.

In the illustrated embodiment, the holding chamber 700 is in the form ofan expandable/collapsible bag (reservoir bag) or similar type structure.According to one aspect of the present invention, the holding chamber700 is in the form of a bi-furcated bag or the like 710 as shown in FIG.6. More specifically, the bag 710 is bi-furcated and has two independentdistinct compartments, namely a first compartment 720 and a secondcompartment 730. Since the two compartments 720, 730 are distinct fromone another (no fluid communication therebetween), the bag 710 has afirst port 740 that forms an entrance and is in fluid communication withthe first compartment 720, as well as a second port 750 that forms anentrance and is in fluid communication the second compartment 730. Aseparating wall or membrane 760 is formed as part of the bag 710 andserves to divide the bag 710 into the first and second compartments 720,730. The body of the bag 710, as well as the separating wall 760, ispreferable formed of a flexible material, such as a fabric that permitsthe bag 710 to either expand as when fluid enters the bag 710 orcontract (collapse) as when the fluid is evacuated from the bag 710. Thefirst port 740 is formed on one side of the separating wall 760, whilethe second port 750 is formed on the other side of the separating wall760. Both the first and second ports 740, 750 are typically defined by ahollow stem or boss.

The first port 740 includes a complementary fastening feature thatpermits it to be sealingly attached to the third leg 540 of theaccessory 500, and similarly, the second port 750 includes acomplementary fastening feature that permits it to be sealingly attachedto the second leg 530. For example, the first and second fasteningfeatures can be in the form of threads that mate with complementarythreads that are part of the legs 540, 530, respectively. Otherfastening means, such as locking means or mechanical fits, such as africtional fit, can likewise be used so long as the accessory 500, andin particular, the second and third legs 530, 540, are sealinglyattached to the bag 710. While, the fastening features can be in theform of threads, it will be appreciated that in many applications andembodiments, the third and second legs 540, 530 and the first and secondports 740, 750 simply mate with one another via a frictional interfacefit between two complementary stems.

The first port 740 of the bag 710 also preferably includes a gas inletport 742 that extends outwardly therefrom and is constructed to attachto a gas source 770. More specifically, the gas inlet port 742 is influid communication with and provides an entrance into the first port740 and is in the form of a tubular structure that has a distal end 744.The end 744 is meant to be attached to the gas source 770 by any numberof techniques, including using a gas conduit, such as tubing or thelike, that extends from the gas source 770 to the gas inlet port 742.The gas source 770 is preferably connected to a control system orregulator or the like that permits the flow rate of the gas source 770to be carefully controlled and varied by means, such as valve assembliesand the like that are associated therewith (e.g., valve assembly withinthe gas conduit).

The gas source 770 can hold any number of different types of gases thatare intended for inhalation by the patient through the accessory 500.

The accessory 500 includes a number of different valve assemblies thatare positioned within the body 510. More specifically, a first valveassembly 800 is disposed within the open second end 514 of the mainsection 516 and in the illustrated embodiment, the first valve assembly800 functions as an exhalation valve. The first valve assembly 800includes a valve element 802 which is positionable between an openposition and a closed position and which can be any number of differenttypes of valve structures so longer as they function in the intendedmanner and provide the desired results. The valve 802 typically seatsagainst a valve seat 804 that is formed at the second end 514 when thevalve 802 is closed. The illustrated valve 802 is a one-way flap valvethat presses against the valve seat 804 on inhalation and completelyoccludes the open second end 514 to prevent any room air entrainment(i.e., not allowing the air from the atmosphere to enter into the mainsection 516 on inhalation). On exhalation, the flap valve 802 moves awayfrom the flap valve seat 804 for the air exhaled by the patient toescape into the atmosphere from the main section 516 by flowing throughthe fourth leg 550 from a mask or the like and then through the mainsection 516 and through the opening formed at the second end 504. Theopen second end 504 is the only means for the exhaled air to escape aswill be appreciated below since the four legs 520, 530, 540, 550 areconnected to devices, are capped or otherwise not open.

A second valve assembly 810 is provided and functions as an inhalationvalve in that the valve moves between an open position and a closedposition depending upon whether the patient is inhaling or exhaling. Thesecond valve assembly 810 is disposed within the body 510 and inparticular, the second valve assembly 810 is disposed within the mainsection 516 at a location between the second leg 530 and the fourth leg550 such that when the second valve assembly 810 is in an open position,fluid can flow from both the first leg 510 and the nebulizer 200, aswell as from the second leg 530 and the second compartment 730 of thebag 710, and into the fourth leg 550 where it can flow into thepatient's mask and into the patient's respiratory system.

The second valve assembly 810 includes a valve element 812 that can beany number of different types of valve structures so long as theyfunction in the intended manner and provide the desired results. Thevalve 812 typically seats against a valve seat 814 that is formed withinthe main section 516 when the valve 812 is closed. The illustrated valve812 is a one-way flap valve that presses against the valve seat 814 onexhalation and completely occludes the main section 516 to prevent anyexhaled air to flow from the mask and fourth leg 550 and into either thesecond compartment 730 of the bag 710 or the first leg 520. Oninhalation, the flap valve 812 moves away from the flap valve seat 814to permit the gas from the nebulizer 200 and/or gas stored in the secondcompartment 730 of the bag 710 to flow into and through the main section516 and into the fourth leg 550 where it flows into the mask to thepatient.

A third valve assembly 820 is provided and is disposed in the third leg540 or it can be provided in the stem that defines the first port 740that is associated with the bag 710. The third valve assembly 820functions as an inhalation valve in that the valve moves between an openposition and a closed position depending upon whether the patient isinhaling or exhaling.

The third valve assembly 820 includes a valve element 822 that can beany number of different types of valve structures so long as theyfunction in the intended manner and provide the desired results. Thevalve 822 typically seats against a valve seat 824 that is formed withineither the third leg 540 or first port 740 when the valve 822 is closed.The illustrated valve 822 is a one-way flap valve that presses againstthe valve seat 824 on exhalation and completely occludes the third leg540 or first port 740 to prevent any exhaled air to flow from the maskand fourth leg 550 and into either the first compartment 720 of the bag710. On inhalation, the flap valve 822 moves away from the flap valveseat 824 to permit the gas from the first compartment 720 of the bag 710to flow into and through the main section 516 and into the fourth leg550 where it flows into the mask to the patient.

While the two compartments 720, 730 of the bag 710 are illustrated ashaving equal or about equal volumes, it will be appreciated that the bag710 can be constructed so that one of the compartments 720, 730 has agreater volume. For example, the first compartment 720 that serves asthe nebulizer holding compartment can have a greater volume than thesecond compartment 730 which receives the supplemental gas to backup thenebulized medication holding chamber.

The first leg 520 is intended to be fluidly attached to the device thatgenerates the aerosol particles (medication) that is delivered to thepatient and preferably, as illustrated, the first leg 520 is fluidlyconnected to the nebulizer 200. More specifically, a connector 212 of aconduit (tube) 210 of the nebulizer 200 is sealingly attached to thefirst leg 520 so that the nebulized medication is delivered through theconduit 210 and into the interior of the first leg 520 and when thesecond valve element 812 is open, the nebulized medication (aerosolparticles) travels the length through the first leg 520 and a portion ofthe main section 516 and through the opening defined by the valve seat814 and into the fourth leg 550 and then into the equipment (facemask)that delivers the medication to the patient. This is the sequence ofevents when the patient inhales. Conversely, when the patient exhales,the second valve element 812 closes; however, the nebulizer 200continues to deliver the nebulized medication through the first leg 520into the interior of the main section 516. Since the second valveelement 812 is closed when the patient exhales prior to the nextinhalation, the nebulized medication can not flow past the valveassembly 810 and into the fourth leg 550 but instead flows through thesecond leg 530 through the second port 750 and into the secondcompartment 730 of the bag 710.

The second compartment 730 of the bag 710 is therefore intended to actas a main reservoir bag in that the second compartment 730 receives andholds the nebulized medication until the patient inhales. The secondcompartment 730 of the bag 710 thus expands until the patient inhales atwhich time the second valve element 812 opens and the inhalation of thepatient draws the nebulized medication out of the second compartment 730into the main section 516 and then into the fourth leg 550 where it isdelivered to the patient.

There are some circumstances where an insufficient amount of nebulizedmedication is present in the second compartment 730 of the bag 710. Thismay result because the flow rate of the nebulizer 200 is insufficientfor the patient as when the patient has a greater body weight than theflow rate setting of the nebulizer 200. When this does occur, thepatient experiences a very uncomfortable feeling in that the patientwill experience an insufficient air flow to the lungs and therefore willbegin to breathe more deeply and rapidly. In other words, the patientmay begin feeling as though they need to gasp for air to breathe.

The present invention overcomes such potential deficiency in air flow tothe patient by providing the first compartment 720 in the bag 710 whichacts as a supplemental air source for the patient due to the firstcompartment 720 being attached to a supplemental gas source, generallyindicated at 770. Preferably, the gas source 770 connects to the stem ofthe first port 740 as shown in the figures; however, it is possible forthe gas source 770 to be directly connected to the first compartment 720of the bag 710. In any event, the gas source 770 is directly and fluidlyconnected to the first compartment 720 and therefore, the gas isdelivered into the first compartment 720. As with the flow of nebulizedmedication into the second compartment 730, the flow of the gas source770 into the first compartment 720 causes the first compartment 720 toexpand as the bag 710 is filled with gas.

It will be appreciated that the gas source 770 serves as a supplementalgas since gas stored in the first compartment 720 is in selective fluidcommunication with the main section 516 and therefore, can flow to thepatient under certain circumstances as discussed below. In other words,if there is insufficient gas in the form of nebulized gas in the secondcompartment 730, when the patient inhales, then the patient will notexperience the above described breathing problems since the firstcompartment 720 is open to the patient through the main section 516 andtherefore, the patient can inhale the supplemental gas that is presentin the first compartment 720 to make up for any shortfall in gas in thesecond compartment 730.

The gas source 770 typically has an associated valve assembly (notshown) that is external to the system and is typically at the gas source770 for controlling the flow rate of the gas source 770 into the firstcompartment 720. The valve assembly is preferably an adjustable valvethat controls the flow rate of the supplemental gas into the firstcompartment 720. Any number of different valve mechanisms are suitablefor this type of application and typically include an adjustable part,such as a dial, that permits the physician to easily alter and changethe flow characteristics. For example, the valve mechanism can includean adjustable member that when manipulated either sequentially closes oropens the opening formed in the conduit that delivers the supplementalgas to the first compartment 720.

Thus, the physician can initially set the valve at one setting which thephysician believes will provide a sufficient supplemental gas flow intothe first compartment 720 based on the physician's past experiences andbased on certain characteristics of the patient, such as the size andweight of the patient. For example, when the patient is a large adult oreven a large child, the flow rate of the nebulized medication into thesecond compartment 730, even when it is set at a maximum flow rate, maynot be sufficient and therefore, this could result in the patientreceiving a low level of air and feeling the above noted discomfort. Thegas source 770 thus supplements the gas flow of the nebulizer 200 andmakes up for any deficiency so that the patient breaths smoothlythoughout the procedure.

When setting the valve, the physician will keep in mind that it may notbe desirable to set the flow rate of the supplemental gas at too high avalue since this will result in the first bag compartment 720 expandingand also, results in the supplemental gas source 770 mixing with thenebulized medication as the patient inhales, thereby causing a decreasein the inhaled concentration of the medication. As mentioned before, itis desirable to try to keep as fixed as possible the concentration ofthe inhaled medication. Since the first compartment 720 is fluidlyconnected to the main section 516 via the third leg 540 and is fluidlyconnected to the first valve assembly 800, any excess build up ofsupplemental gas in the first compartment 720 can be vented through thefirst valve 802 each time the patient exhales since the second valveassembly 810 closes when the patient exhales and the supplemental gascan not flow past the second valve assembly 810 toward the other legsand the second compartment 730 of the bag 710.

In the event that the initial setting of the valve is not optimal inthat the too much supplemental gas is being delivered to the first bagcompartment 720 or too little supplemental gas is being delivered to thefirst bag compartment 720, the physician simply needs to make thenecessary adjustment to the valve to either immediately reduce orincrease, respectively, the supplemental gas flow into the first bagcompartment 720. This can be done by simply turning or otherwisemanipulating the valve. It is also very easy for the physician todetermine whether the flow rate of the supplemental gas source 770 isoptimal since the physician can observe the bag 710 and moreparticularly, can observe whether either the first bag compartment 720,the second compartment 730 or both compartments 720, 730 appear to beexcessively collapsed (thus indicating an increase in flow rate isneeded) or excessively expanded or extended (thus indicating a decreasein flow rate is needed). The physician can simply and immediately alterthe flow rate and thus, the accessory 500 is tailored to be used with awhole range of different types of patients, from small infants up tolarge adults.

A supplemental gas valve assembly is preferably provided for controllingthe flow of the supplemental gas out of the first compartment 720 andinto the third leg 540 and more particularly, to permit flow of thesupplemental gas from the first bag compartment 720 into the third leg540, through the main section 516 and ultimately to the patient when thepatient inhales and conversely, preventing the flow of supplemental gasfrom the first bag compartment 720 into the third leg 540 when thepatient exhales. It will also be appreciated that when valve assemblycloses during exhalation, the exhaled air that includes waste gases isnot permitted to flow into the first bag compartment 720 where it couldthen be drawn into the patient at the next inhalation movement of thepatient.

Now referring to FIG. 7 in which another embodiment of the accessory 800is illustrated. The accessory 800 is similar to the accessory 500 andtherefore, like elements are numbered alike. In the accessory 800, thefirst leg 520 no longer is formed at one end of the main section 516 butrather is formed in the middle of the main section between the fourthleg 550 and the second leg 530 which is located closer to one end of themain section 516. In this design, the first leg 520 is closer to thefourth leg 550 and since the first leg 520 is still fluidly connected tothe nebulizer 200, the length of the gas flow path from the nebulizer200 to the face mask is less in this embodiment than in the embodimentof FIG. 6 due to the relative positions of the first and fourth legs520, 550.

Since the first leg 520 is not formed at the end of the main section 516in this embodiment, the main section 516 has a closed end 517 (e.g., theend 517 can be capped or can the section 515 can be formed so that thisis a closed end).

As shown, the first leg 520 is disposed between the second valveassembly 8S-0 and the second leg 530 and in particular, the first leg520 communicates with the interior of the main section 516 at a locationthat is near the second valve element 812. It will be appreciated thatin this embodiment, the nebulizer 200 is located in front of/downstreamfrom the gas flow from the second compartment 730 of the bag 710 and thepresent applicants have discovered that the placement of the nebulizer200 in this location results in improved performance and improved drugdelivery since the aerosolized medication is located closer to the facemask as measured along the gas flow path. In addition, this location forthe nebulizer 200 permits the gas flow from the second compartment 730of the bag 710 to assist in carrying the aerosolized medication to thefourth leg 550 and into the patient's mask or the like. In other words,the gas flow from the second compartment 730 acts to entrain theaerosolized medication that is flowing through the first leg 520 fromthe nebulizer 200.

The operation of the components is the same in this embodiment as in theother embodiments. For example, the valve assemblies 800, 810, 820operate the same in both embodiments. The first leg 520 is positionedclose to the second valve assembly 810 such that once the valve element812 opens upon inhalation, the gas and aerosolized medication from thenebulizer 200 flows through the valve element 812 and into the fourthleg 550 to the patient.

It will also be appreciated that in each of the embodiments of FIGS. 6and 7, the first leg 520 can be capped or otherwise sealed as whennebulizer 200 is not used with the respective accessory. In this design,the bag 710 can serve as a means for delivering a gas, such as oxygen orheliox, etc., to the patient. In particular, gas source 770 provides gasthe is routed through the first compartment 720 of the bag 710 and intothe main section 516 and then into the fourth leg 550 to the face mask.

Having described embodiments of the invention with reference to theaccompanying drawings, it is to be understood that the invention is notlimited to those precise embodiments, and that various changes andmodifications may be effected therein by one skilled in the art withoutdeparting from the scope or spirit of the invention as defined in theappended claims.

1. An accessory for an aerosol inhalation system comprising: a mainconduit body having an outlet end for placement close to a mouth of apatient; a first leg conduit in fluid communication with the mainconduit body and including a distal end; a second leg conduit in fluidcommunication with the main conduit body and including a distal end, thesecond leg conduit being spaced apart from the first leg conduit; afirst port formed as part of the first leg conduit for attachment to adevice that generates aerosol particles as a means for deliveringmedication to the patient; a second port formed as part of the first legconduit; a third port formed as part of the second leg conduit; aholding chamber having a first compartment and a second compartmentseparated from the first compartment, with the first compartment beingsealingly and fluidly coupled to the second port and the secondcompartment being sealingly and fluidly coupled to the third port; andan arrangement of valves such that when the patient exhales, the firstleg conduit is sealingly closed off from the main conduit body and thesecond leg conduit resulting in the aerosol particles flowing into andbeing held in the first compartment of the holding chamber andconversely, when the patient inhales, the first leg conduit is opened tothe main conduit body and in fluid communication with the second legconduit resulting in the aerosol particles delivered through the firstport being delivered to the patient.
 2. The accessory of claim 1,wherein the main conduit body, the first leg conduit and the second legconduit are in the form of a Y-shaped connector.
 3. The accessory ofclaim 1, wherein the first leg conduit and the second leg conduit aresubstantially parallel to one another and are fluidly joined at the sameends to the main conduit body.
 4. The accessory of claim 1, wherein thefirst, second and third ports are all formed on the same face of theaccessory.
 5. The accessory of claim 1, wherein the first port is formedcloser than the second port to the distal end of the first leg conduit.6. The accessory of claim 1, wherein the second and third ports areformed the same distance from the distal ends of the first and secondleg conduits, respectively.
 7. The accessory of claim 1, furtherincluding cap sealingly closing off the distal end of the first legconduit.
 8. The accessory of claim 1, wherein the arrangement of valvesincludes an exhalation valve that is disposed in and seals off thedistal end of the second leg conduit, the exhalation valve movingbetween an open position when the patient exhales, thereby opening thesecond leg conduit to atmosphere and a closed position when the patientinhales.
 9. The accessory of claim 8, wherein the exhalation valvecomprises a one way valve.
 10. The accessory of claim 1, wherein thearrangement of valves includes an inhalation valve that is disposed inthe first leg conduit such that the first and second ports are locatedbetween the inhalation valve and the distal end thereof.
 11. Theaccessory of claim 10, wherein the inhalation valve is formed at aninterface between the main conduit body and the first leg conduit. 12.The accessory of claim 10, wherein the inhalation valve comprises a oneway valve.
 13. The accessory of claim 1, wherein the device comprises anebulizer that delivers the aerosol particles at a prescribed flow rate.14. The accessory of claim 1, wherein the holding chamber is defined bya reservoir bag with the first and second compartments defined thereinand separated from one another by a bi-furcating wall, the reservoir bagbeing formed of a expandable/collapsible material.
 15. The accessory ofclaim 14, wherein the reservoir bag includes a fourth port integrallyformed therewith and fluidly in communication with the first compartmentand a fifth port integrally formed therewith and fluidly incommunication with the second compartment, each of the fourth and fifthports including fastening features that permit them to be sealinglymated with the second and third ports.
 16. The accessory of claim 14,further including: a supplemental gas port in fluid communication withthe second compartment and for attachment to a supplemental gas sourcethat delivers a prescribed amount of gas to the second compartment tosupplement the flow of the aerosol particles through the first port. 17.The accessory of claim 16, further including a third valve that isassociated with one of the fifth port and third port, the third valvemoving between an open position when the patient inhales causing thesecond leg conduit and second compartment to be in fluid communicationand a closed position when the patient exhales, thereby fluidly closingoff the second compartment from the second leg conduit.
 18. Theaccessory of claim 17, wherein the third valve is a one-way valve andwherein, as the patient inhales, the supplemental gas stored in thesecond compartment is free to flow through the second leg conduit intothe main conduit body to the patient to supplement the aerosol particlesflowing through the first leg conduit.
 19. The accessory of claim 17,wherein the third valve is formed in the fifth port at a location thatis above an inlet of the supplemental gas into the fifth port such thatthe inlet is between the fifth valve and the second compartment.
 20. Anaerosol inhalation system comprising: at least one device for producingaerosol particles for delivering medication to a patient through a pieceof equipment in communication with a respiratory system of the patient;an accessory for interfacing between the at least one device and thepiece of equipment, the accessory comprising: a main conduit body havingan outlet end connected to the piece of equipment; a first leg conduitin fluid communication with the main conduit body and including a distalend; a second leg conduit in fluid communication with the main conduitbody and including a distal end, the second leg conduit being spacedapart from the first leg conduit; a first port formed as part of thefirst leg conduit and connected to the at least one device; a secondport formed as part of the first leg conduit; a third port formed aspart of the second leg conduit; a holding chamber having a firstcompartment and a second compartment separated from the firstcompartment, with the first compartment being sealingly and fluidlycoupled to the second port and the second compartment being sealinglyand fluidly coupled to the third port; and an arrangement of valvesincluding a first valve for opening up the first leg conduit to the mainconduit body under a first prescribed event and closing the second legconduit to the main conduit body under a second prescribed event,wherein a second valve is provided for venting the second leg conduitunder the second prescribed event; and a supplemental gas source incommunication with the second compartment and including a third valvefor controlling flow of the supplemental gas into the second leg conduitfrom the second compartment, wherein the supplemental gas is permittedto flow into the second leg conduit under the first prescribed event andprevented under the second prescribed event.
 21. The system of claim 20,wherein the main conduit body, the first leg conduit and the second legconduit are in the form of a Y-shaped connector.
 22. The system of claim20, wherein the first leg conduit and the second leg conduit aresubstantially parallel to one another and are fluidly joined at the sameends to the main conduit body.
 23. The system of claim 20, wherein thefirst, second and third ports are all formed on the same face of theaccessory.
 24. The accessory of claim 20, further including capsealingly closing off the distal end of the first leg conduit.
 25. Thesystem of claim 20, wherein the first prescribed event is when thepatient inhales and the second prescribed event is when the patientexhales.
 26. The system of claim 24, wherein the first valve comprisesan inhalation valve that is disposed in the first leg conduit such thatthe first and second ports are located between the inhalation valve andthe distal end thereof, the first valve moving between an open positionwhen the patient inhales and a closed position when the patient exhales,the second valve comprising an exhalation valve that is disposed in andseals off the distal end of the second leg conduit, the exhalationmoving between an open position when the patient exhales, therebyopening the second leg conduit to atmosphere and a closed position whenthe patient inhales.
 27. The system of claim 26, wherein each of thefirst and second valves comprises a one-way valve.
 28. The system ofclaim 20, wherein the device comprises a nebulizer that delivers theaerosol particles at a prescribed flow rate.
 29. The system of claim 20,wherein the holding chamber is defined by a reservoir bag with the firstand second compartments defined therein and separated from one anotherby a bi-furcating wall, the reservoir bag being formed of aexpandable/collapsible material.
 30. The system of claim 20, whereinduring the first prescribed event by the patient, the supplemental gasstored in the second compartment is free to flow through the second legconduit into the main conduit body to the patient to supplement theaerosol particles flowing through the first leg conduit.
 31. The systemof claim 20, wherein the third valve is a one way valve that permits thesupplemental gas from flowing into the second leg conduit when thepatient inhales and prevents the supplemental gas from flowing into thesecond leg conduit when the patient exhales gas, the exhaled gas beingprevented from flowing into the first compartment by means of the firstvalve and into the second compartment by means of the third valve. 32.An accessory for an aerosol inhalation system comprising: a main conduitbody having an outlet port for placement close to a mouth of a patient;first, second and third legs in fluid communication with the mainconduit body and located in series along a longitudinal length of themain conduit body; a first port formed as part of the first leg forattachment to a device that generates aerosol particles as a means fordelivering medication to the patient; a second port formed as part ofthe first leg conduit; a third port formed as part of the second legconduit; a holding chamber having a first compartment and a secondcompartment separated from the first compartment, with the firstcompartment being sealingly and fluidly coupled to the third port andthe second compartment being sealingly and fluidly coupled to the secondport; and an arrangement of valves such that when the patient exhales,the first, second and third legs are sealingly closed off from the firstsection of the main conduit body resulting in the aerosol particlesflowing into and being held in one compartment of the holding chamberand conversely, when the patient inhales, the first leg is opened to themain conduit body and in fluid communication with the second leg, bothof which are in fluid communication with the outlet port of the mainconduit body resulting in the aerosol particles being delivered to thepatient.
 33. The accessory of claim 32, wherein the outlet port islocated between the second and third ports and between an exhalationvalve at one end of the main conduit body and a first inhalation valvelocated in the main conduit body between the second and third legs and asecond inhalation valve that is disposed in the third leg.